Effect of cultural and intergrated methods of weed control on cotton, intercrop yield and weed-control efficiency in cotton-based cropping systems

A field experiment was conducted on clayey soils during the rainy seasons (kharif) of 1999–2000 to 2002–03 at Parbhani to find out the effective and economic method of weed control for cotton (Gossypium spp.) + blackgram [Phaseolus mungo (L.) Wilczek] and cotton + soybean [Glycine max L.) Merr.] intercropping systems. In cotton + blackgram intercropping, integrated weed management with pre-emergence application of oxyfluorfen @ 0.100 kg/ha or pendimethalin @ 0.75 kg/ha supplemented with weeding and hoeing at 6 weeks after sowing proved as effective as that of 3 hand-weedings and hoeings at 3, 6 and 9 weeks after sowing (recommended cultural practice). This treatment also helped reduce the weed population and weight of dry weeds at first picking with highest weed-control efficiency, enhanced the cotton-equivalent yield and net monetary returns, and proved more economical than the recommended cultural practice. In cotton + soybean intercropping, preemergence application of oxyfluorfen @ 0.100 kg/ha supplemented with hand-weeding and hoeing at 6 weeks after sowing proved equally effective in controlling the population and dry weight of weeds, and was as economical as that of cultural practice of 3 hand-weedings and hoeings at 3, 6 and 9 weeks after sowing.